Field of the Invention
Embodiments of the present invention relate to a lighting device, and in particular to a lighting device structure which makes it possible to make the whole thickness thinner as such to obtain a high illuminating efficiency in such a way to remove a light guide plate and makes it possible to obtain an effect that the shape and a 3D effect of light change by forming a protrusion optical pattern.
Description of Related Art
The LED (Light Emitting Diode) device is directed to converting an electric signal into infrared ray or light using the natures of a compound semiconductor. Different from a fluorescent lamp, it does not use any harmful substances such as mercury, which results in less environment contamination, along with an advantage that service life is longer as compared to a conventional light source. It also consumes low electric power as compared to a conventional light source, and visibility is good thanks to a high color temperature and no glaring.
The lighting device is currently changing from a type that a conventional incandescent lamp and a conventional fluorescent lamp are used as a light source to a type that a LED device is used as a light source. In particular, there is provided a lighting device which performs a plane light emitting function by using a light guide plate as disclosed in the Korean patent publication number 10-2012-0009209.
The light guide plate is used as a necessary element of the conventional lighting device 1; however it has a limit in making a thinner product owing to the thickness itself of the light guide plate. Since the material of the light guide plate is not flexible, it cannot be applied to the external housing 50, etc. which has curved surfaces, so the product design and the design changes are not easy.